You can also blame screwed up computer systems not programmed to eliminate items like 4 cents due, thanks to the inefficiency and stupidity of those who program them or use them.

Years back I cancelled an order I had made at a major retailer in the States. I got confirmation of the cancellation. But they had a glitch in their computer program which showed me owing them $0.00. When no payment was made, they threatened that penalties would accrue. This went on for months despite my proving that no merchandise had been purchased. They told me it was going to a debt collection agency. The only way this got settled was by my writing out a check for $0.00 and hand delivering it to the business office of the store. And yes, they deposited this check. And when it came to the bank to be cleared the bank called to ask why I was playing a game with a check made out for nothing. Why? Because some people cannot use the brains they were born with.

This happened to me in Israel with the gas company. I got a bill for -28 shekels, so of course I ignored it, thinking they woudl deduct the 28 shekels from my next bill. Then I got a red notice warning me that my gas would be cut off if I did not pay -28. So I ignored it. And my gas got cut off.

When I called the gas company in an unholy fury, they thought it was hilarious, apologised for the computer glitch and graciously agreed to reconnect me for no cost. (I should think so too!). My next bill came with a 28 shekel cheque. I ought to have had it framed. :-)

In the early 70's When I was a teenager I was just learning computers and puchcard based batch processing was still the norm. Whenever we got our Con Ed (NYC electric) bill it came with a punchcard that was to be returned with the payment.

Out of curiosity, one time I passed the punchcard through a keypunch machine and read it just to see what was on it. I was able to recognize some of the data fields such as customer Id and amount due because they were printed on the accompanying paper bill as well.

Being in an impish mood I made a change to the punch card. I puched a minus sign into the column just before the amount changing something like 183.50 to -183.50. I gave it back to my mother (who would have been horrified had she known that I was tampering with the system) and she wrote the check and mailed the bill.

Nothing ever happened because of this. Maybe it generated an exception in their data center but we never got any feedback. I suppose that punch card sabotage was a factor that they had to take into account when designing the work flow for their system.

Reminds me also of the bank robber who made his money by slipping pre-printed (magnetic ink with his account number!) deposit slips into the counter at the bank and waited for someone to come along and make a deposit into his account. They only caught him by depositing an odd amount e.g. seven cents and waiting for a seven cent deposit to go astray.